The present invention relates to a fire detector and more particularly to the construction of the body and the base in the fire detector wherein the body is comprised of a cover part and a hood part and which contains therein fire detecting means and electrical circuits, the base being adapted to detachably fasten the body thereto.
In general, a fire detector comprises a body in which are received fire detecting means to detect the appearance of a fire and electrical circuits to convert the output of the fire detecting means into electrical signals, etc. and a base which is adapted to be installed on the surface of a ceiling, etc. in order to detachably fasten the body to the surface of a ceiling, etc.
In this case, in order to facilitate the cleaning of the fire detecting means and the replacement of the elements of the electrical circuits, etc. during maintenance and inspection of the fire detector the body comprises a cover part which is provided with claw members and a hood part which is provided with stepped portions to be engaged by the claw members.
However, if the body thus comprising a cover part and a hood part is so constituted that they can be easily separated from each other during maintenance and inspection of the fire detector the cover part may be apt to easily come off from the hood part when fastening the body to the base due to the shock, vibrations, etc. to which the body may be possibly subjected, causing problem. Conversely, if the cover part and the hood part are so constituted that it is hard for the cover part to come off even when subjected to shock, vibration, etc. one or both of the cover and the hood parts may be easily damaged, or broken, etc. when it is attempted to disconnect them from each other at the time of maintenance, inspection, etc. of the fire detector, giving rise to other problems.